Holistic Optimization of Real-Time IEEE 802.15.4/ZigBee Networks

IEEE 802.15.4 is a global standard designed for emerging applications in low-rate wireless personal area networks (LR-WPANs). The standard provides nice features such as a beacon-enabled mode and guaranteed time slots for real-time data delivery. However, how to optimally operate those features is still an open issue. For the optimal operation of the features, this paper proposes a holistic optimization method that jointly optimizes three cross-related problems: (1) cluster-tree construction, (2) nodes' power configuration, and (3) duty-cycle scheduling. Our holistic optimization method finds the solution for the three problems such that all the real time packets can be delivered within their deadlines in the most energy-efficient way. Our simulation study shows that, comparing with existing methods, our holistic optimization can guarantee the on-time delivery of all real-time packets while significantly saving the energy and hence significantly increasing the network lifetime.